1. Field of the Invention
The present invention relates to a method for inserting the treatment tool into a biliary tract from a digestive tract.
2. Description of the Related Art
In the related art, various kinds of endoscopes are used at the time of observing internal organs of a subject such as a patient. Among these endoscopes, there is a known ultrasound endoscope that transmits ultrasound waves to an observation target and receives echoes of the ultrasound waves reflected at the observation target. An ultrasound image of the observation target is generated by applying predetermined signal processing to the ultrasound echoes received by the ultrasound endoscope, thereby achieving to perform diagnosis and treatment while observing the ultrasound image.
As a treatment method using the ultrasound endoscope, there is a method of inserting a treatment tool in which the treatment tool is inserted into a stenosis at a biliary tract from a digestive tract. According to this method of inserting a treatment tool, for example, a stent is inserted into a stenosis portion Cbst of the biliary tract (common bile duct Cb) by using, for example, an ultrasound endoscope (EUS scope) and a scope for a duodenum (JF scope). FIGS. 1 to 6 are explanatory diagrams for a method of inserting a treatment tool in the related art, and are the diagrams for explaining the method of inserting a treatment tool in which the treatment tool is inserted into the biliary tract from the digestive tract. First, as illustrated in FIG. 1, an EUS scope 200 is inserted into a duodenum Dd inside a subject, and an image is captured from the duodenum Dd to a common bile duct Cb by ultrasound waves, and then a bile duct is punctured with a cylindrical-shaped puncture needle TD100. The technology of performing puncture while observing an ultrasound image by the EUS scope is referred to as an endoscopic ultrasound-guided fine needle aspiration (FNA).
After that, a contrast agent is injected into the common bile duct Cb via the puncture needle TD100, and a guide wire GW100 is inserted into the common bile duct Cb via the puncture needle TD100 while performing radiographic visualization. Then, a distal end of the guide wire GW100 is placed inside the duodenum Dd via a duodenal papilla Dp (refer to FIG. 2).
After placement of the distal end of guide wire GW100 inside the duodenum Dd, the puncture needle TD100 and the EUS scope 200 are taken out from the inside of the subject while leaving the guide wire GW100 inside the subject (refer to FIG. 3). In a state that only the guide wire GW100 is left inside the subject, a JF scope 201 is inserted into the duodenum Dd (refer to FIG. 4) and the guide wire GW100 extending from the duodenal papilla Dp is pulled into the JF scope 201 (refer to FIG. 5). This results in a state that the guide wire GW100 extends from the JF scope 201 and the other end of the guide wire GW100 is placed inside the common bile duct Cb. A cylindrical-shaped stent ST100 is placed at the duodenal papilla Dp and the stenosis portion Cbst via the JF scope 201 and the guide wire GW100 in this state, thereby achieving a state that the stenosis portion Cbst is expanded by the stent ST100 (refer to FIG. 6). Treatment can be performed inside the biliary tract including the common bile duct Cb through the stent ST100.
Examples of the most general method of inserting a treatment tool into the stenosis at the biliary tract include a technique of “endoscopic retrograde cholangiopancreatography (ERCP)” in which a cannula is inserted into the duodenal papilla Dp while visualizing an endoscopic optical image by using the JF scope, and a contrast agent is injected into the bile duct, etc. via the cannula so as to make a state that the biliary tract, etc. can be observed by radiographic visualization. According to this technology, for example, the guide wire GW100 is placed in the common bile duct Cb via the cannula while the cannula is inserted into the duodenal papilla Dp, and the cylindrical-shaped stent ST100 is placed in the duodenal papilla Dp and the stenosis portion Cbst via the JF scope 201 and the guide wire GW100. However, the method of inserting a treatment tool by utilizing this ERCP is known as a highly difficult method among the endoscopic procedures, and there may be a case where the guide wire GW100 cannot be inserted into the common bile duct Cb. As a replaceable procedure, there is a method of inserting a treatment tool by using the above-described EUS scope.